Presymptomatic treatment of type 1 spinal muscular atrophy – A literature review

• Autor(a) principal: Vieira, Paula Manuel
• Data de Publicação: 2024
• Outros Autores: Garrido, Cristina, Santos, Manuela
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: https://doi.org/10.25753/BirthGrowthMJ.v32.i4.28929
• topic: Review Articles

Spinal muscular atrophy (SMA) is the leading monogenic cause of childhood death and SMA1 is its most common form. It is caused by a pathogenic variant in the survival motor neuron (SMN) 1 gene that results in the lack of a functional SMN protein. Patients suffer from a rapid and irreversible loss of motor neurons. Symptoms include weakness, hypotonia, and delayed or absent achievement of early motor milestones, never reaching the ability to sit independently. Respiratory muscle weakness, tongue fasciculations, and poor swallowing reflexes are common. Diagnosis is based on molecular genetic testing. To ensure earlier diagnosis, newborn screening (NBS) programs have been implemented in some countries and are extremely reliable. Before the development of disease-modifying therapies, the natural course of the disease led to rapid weakness with respiratory failure and death before the age of two in most patients. Disease-modifying drugs reduce the need for respiratory and nutritional support and lead to motor gains. Greater improvements are seen in patients treated early, before symptoms become apparent. These findings underscore the need for NBS programs, as early treatment is highly effective in reducing the need for supportive therapy, thereby reducing the overall cost of therapy.